Electric vibrator



2 Sheets-Sheet 1 w. H. HoRscH ELECTRIC VIBRATOR Filed Feb. 27. 1933 Nov.6, 1934.

Jay/WW Nov. 6, 1934. w. H. HORSCH' ELECTRIC VIBRATOR Filed Feb. 27. 19332 Sheets-Sheet 2 Patented Nov. 6, 1934 UNITED STATES ELECTRIC VIBRATQRWalter H. Horsch, Wheaton, lllL, assignor to Massey Concrete ProductsCorporation, Chicago, 111., a corporation of Virginia ApplicationFebruary 27, 1933, Serial No.-658,85l

3 Claims.

The present invention relates to electric vibrators, and is particularlyconcerned with electric vibrators adapted to be used for high frequencyvibration of concrete and other molded products.

55 The vibrator is capable, however, of general application, and I donot wish to limit myself to any particular use of the apparatus.

One of the objects of the invention is the provision of an improvedvibrator which may be more quickly and conveniently attached to anddetached from the concrete forms with which the vibrator is intended tobe used'. withoutnecessity for using any wrenches or other tools andwithout any possibility of the vibrator jarring loose.

Another object of the invention is the provision of an improved vibratorwhich is adapted to vibrate at a higher frequency than any of thedevices of the prior art and which is adapted to provide balancedvibrations by virtue of the improved structure of the vibrator.

Another object of the invention is the provision of an improved vibratorstructure of the rotary type, by means of which the eccentric thrustwhich is placed upon the rotating shafts which support the eccentricweights, is eliminated and the armature shaft is not subjected to eccentrio forces.

Another object of the invention is the provision of an improved vibratorwhich is sturdy, capable of economical manufacture and also capable oflong use without necessity for replacement or repair, and which has aminimum of moving parts I so as to reduce friction and reduce thepossibility of parts wearing out.

Another object of the invention is the provision of an improved vibratorstructure having separately mounted eccentrically supported weights andhaving an improved mode of drive connection between these weights andthe motor whereby centrifugal action upon the universal joint is reducedto a minimum and the joint is capable of operat on at a higher speed.

Another object of the invention is the provision type employingeccentrically mounted rotating of an improved high frequency vibrator ofthe undue strain upon the electric motor and its bearings.

Other objects and advantages of the invention will be apparent from thefollowing description and the accompanying drawings, in which similar 60characters of reference indicate similar parts throughout the severalviews.

Referring to the drawings, of which there are two sheets:

Fig. 1 is a front elevational view of an electric vibrator constructedaccording to the present invention and applied to a concrete pipe formof large size;

Fig. 2 is a transverse horizontal sectional view taken on the plane ofthe axis of the motor shaft, with the motor shaft in plan, showing thedetails of construction of the vibrator and its mode of attachment;

Fig. 3 is a sectional view taken on the plane of the line 33 of Fig. 2,showing the details of con- 'struction and shape of the eccentricallymounted rotating weight;

Fig. 4 is a fragmentary sectional view taken on the plane of the-line 33of Fig. 2, showing the details of construction of the handle;

Fig. 5 is an elevational view of the eccentric weight as viewed from theend of the weight, looking toward the supporting shaft;

Fig. 6 is an exploded fragmentary view in perspective of the details ofconstruction of the 35 motor shaft and weight supporting shaft and theconnecting universal joint;

Fig. 7 is a fragmentary sectional view taken on the plane of the line7-7 of Fig. 1, showing the details of the mode of attachment of thevibra- 9 tor to the concrete pipe form;

Fig. 8 is a fragmentary front elevational view of the supportingapparatus on the pipe, with the vibrator removed; a

Fig. 9 is a fragmentary sectional view of one end of another type ofvibrator which is adapted to produce vibrations in a predetermineddirection;

Figs. 10 and 11 are two diagrams showing the' relative arrangements ofthe eccentric weights of the vibrator of Fig. 9, which result in theproduction of vibrations in predetermined directions. r

Referring to Fig 1, 10 indicates'in its entirety a metal form for aconcrete pipe consisting of two halves provided with radially extendingflanges 11 which are secured together to form the outer shell of thepipe. The form is provided with an appropriate core, and preferablysupported with the bell end of the pipe upward.

The form is supported upon a truck 12 consisting of a platform 13carried by flange wheels 14 guided upon rails 15 so that one form afteranother may be brought into position beneath the concrete mixing anddischarging apparatus.

Fixedly supported upon the form is a con crete vibrator, indicated inits entirety by the numeral 16, and the concrete vibrator 16 ispreferably of the rotary type comprising a motor and one or moreeccentrically mounted weights rotated by the motor in order to producevibration.

In order to provide a vibrator capable of vibration at a higher rate ofspeed, it is necessary to increase the speed of rotation of the motor,and therefore the motor is preferably an induction motor, such as athree phase induction motor which does not require any commutator orbrushes, and therefore the possibility of excessive wear and sparking atbrushes is eliminated.

This problem would otherwise become very serious at high rates of speed.

The three phase induction motor of the vibrator 16 is energized throughthe three supply conductors 17, which preferably lead to a frequencychanger 18 which is energized by conductors 19 leading to the 60 cyclealternating current power supply.

For example, one embodiment of the invention comprises a ninety cycle110 volt, three phase motor of approximately one and one-half horsepower rating, capable of rotation at 5300 R. P. M. By increasing thefrequency of the energizing current, that embodiment of the vibratormight be caused to vibrate at. any multiple of forty-five or sixtycycles, or any desired frequency, by means of appropriate energizingcurrent.

The present vibrators are capable of producing vibrations at frequenciesas high as from eight thousand to twelve thousand R. P. M., theprincipal difficulties being the provision of parts of suflicientstrength to withstand the higher rates of frequencies.

Referring to Figs. '7 and 8, these are views showing the mode ofattachment of the vibrator on the form. The form 10, which is filledwith concrete 20, may be provided with a pair of vertically extending"angle irons 21, 22, each having one flange riveted, welded, or otherwisefixedly secured to the form.

Theangle irons have the-opposite flange extending outwardly from theform 10, and these transverse flanges may be formed with laterallyprojecting feet 23 at each end. The feet 23 may be bolted, riveted, orwelded to the outwardly projecting flanges 24 of circumferentiallyextending angle irons 25, 26 fixedly mounted. on the form 10.

A vertically extending channelled member 27 of stock shape may beprovided with a body 28 and side flanges 29 and 30, and the flanges 29and 30 may be bolted to the outwardly projecting.

flanges of the angle irons 21 and 22, thereby fixedly securing thechannelled member 27 to the form.

' The channelled member 27 fixedly supports a tapered metal member 31which is provided with a flat rear side 32 for engagement with the body28 of the channel 27. The tapered metal member 31 may be provided withtransverse bores 33 for passing bolts 34, the heads of which arecountersunk below the forward surface 35 of the metal member 31.- Themetal member 31 has outwardly flaring sides 36, 37, the angularity ofwhich in a horizontal plane is complementary to the angularity of therecess ina socket member 38.- The flaring surfaces 36 and 37, however,also slope outward toward the bottom at a predetermined angle, which hasbeen carefully determined by experiment and use. If this angle is notsufficient, the recessed complementary member 38 will be wedged sotightly on the member 31 that it will be impossible to remove it, and ifthe angle is greater than a predetermined amount the wedging action'willnot be sufficient, and the vibrator will ride upward on its support andbecome loose. If this angularity is too great, so that sufficientwedging action is not present, it is necessary to use a securing deviceon top of the member 31 to engage the top of the member 38 and preventthe vibrator from riding upward and becoming loose.

Such a securing member might take the form of a plate bolted to themember 31, but many of the advantages of the securing device are lost ifit is necessary to screw or unscrew bolts effecting a fastening orunfastening of the vibrator from the form.

It is the object of the present invention to avoid the use of any suchdevices, which, however, have been tried and eliminated by the use of apredetermined angle. The taper of the member 31 should preferably beabout two degrees from the vertical or within the range of one andone-half to two and one-half degrees. This taper results in a firmwedging of the so-called keystone 31 in its socket without the vibratorriding upward and becoming loose during the vibration.

The device is still capable of being separated from the form by means ofa sharp blow with a hammer, so that the vibrator may be quickly detachedfrom any form and attached to another form.

.The socket member 38 is, of course, provided with diagonally andinwardly extending surfaces 39, 40, which also flare outwardly towardthe A such as a three phase alternating current induction motor, but insome cases single phase or two phase motors may be used with appropriatestarting windings, or any type of motor might be applied which isconsidered suitable.

The motor preferably is of a type not having any commutator, as higherspeeds may be attained when commutator troubles are eliminated. Therotor 45 may consist of a motor shaft 46 with an appropriate core 47 oflaminations, provided with suitable squirrel cage windings and fixedlymounted on the shaft 46. The shaft 46 may be provided with reduced endsforming annular shoulders 48 for engaging one side of the ball bearingrace 49which supports the balls 50 engaging the complementary outer'race 51.

The bearings used are preferably of the self-,-

alignin ".vpe and preferably of the sealed type provided with an oilseal for preventing thelubricant from escaping from the bearing, but, ifnecessary, the motor housing may be provided with grooves 52 forreceiving an oil sealing member 53 surrounding the motor shaft 46.- Allof the anti-friction bearings used are preferably of the sealed type.The construction at the opposite end of the motor shaft in Fig. 2 isexactly the same, and therefore need not be described in detail, and ingeneral both ends of the vibrator may be similar, and therefore only oneend will be described.

The field windings 54 are carried by a laminated field core 55 having asuitable number of poles, and the laminations of the field core 55 maybe clamped between two clamping members 56, 57, to which they may besecured by rivets and bolts or other securing devices. The clampingmembers 56 comprise annular metal members having outer cylindricalsurfaces and having flat surfaces engaging the laminations 55 and withthe laminations 55 the clamping members 56, 57 form the outer casing ofthe middle part of the motor.

The side surfaces of the members 56, 57 are preferably provided withflat annular surfaces 58, 59 which are separated by a' cylindricalshoulder 60 adapted to align the end housing member with the medial partof the motor housing. The end housing member 61 consists of a cast metalmember which is formed with an inwardly extending boss 62 having a bore63 for passing the motor shaft 46.

The boss 62 is also formed with an annular shoulder 64 and an enlargedrecess 65 for receiv ing the outer race 51 of the motor anti-frictionbearing, and the recess 65 tapers outward at 66 to communicate with alarger recess 67 having an annular shoulder 68 against which is seated asimilar but larger type of anti-friction bearing 69 spaced from themotor bearing 70;

The motor end plate 61 is provided with an outwardly extending boss 71which is formed with the socket 67, shoulder 68 and tapered intermediateportion 66. The annular end plate 61 is also formed with a. plurality ofthreaded bores 72 preferably equally spaced about its periphery andadapted to receive the threaded bolts 73 which secure thevibratorhousings 74 to the motor housing. The end plates 61 are also providedwith symmetrically located and equally spaced transverse bores 75which-register with the bores 76 passing through the clamping members.56, 57 and laminations 55 for receiving the assembly bolts 77, whichpass all the way through the motor housing and secure the end plates,clamping members and field core together.

At the opposite sides of the housing, the end plates 61 are providedwith sockets 78 surrounding the bores 75for receiving the flat ends 79of a U shaped handle 80. The sockets 78 may be substantiallyrectangular, having fiat sides 81, 82

engaging the flat sides of the ends 79 of the handle, and when securedby the bolt 77, which passes through the end of the handle, as wellasthe motor housing, thehandle 80 is also secured against rotation.

Two of the handles 80 are preferably provided, one at each side of thehousing, but anynumber of handles maybe utilized. 1

These handles may also be employed for hooking or otherwise fasteninglifting devices. I

The end plates 61 are provided with the rearwardly projecting flanges81', upon which are formed the surfaces 39, 40, 41, 42, which form thesocket for the keystone 31, previously described.

The vibrator housing 74 comprises a cast metal member of substantiallycup shape, one of the housings being preferably provided for each end ofthe vibrator. This vibrator is preferably provided with an eccentricweight 82, 83 at each end of the motor shaft. The vibrator housing isformed with a substantially cylindrical socket 84,.capable of receivingthe outer race of a second vibrator shaft bearing 85, which may be ofthe same type as the bearings previously described.

The vibrator shaft 86 is shown in detail at the right of Fig. 2, and itcomprises a short shaft having reduced ends 87, 88, the ends 87, .88supporting the inner races of the bearings 69, 85 which are seatedagainst the annular shoulders 89, 90. All of the races of the bearingsin this device are preferably a close frictional fit with the partswhich they engage, the outer races being fixedly mounted by a frictionalfit in their sockets, andthe inner races being fixedly mounted on theshaft by a close frictional fit on the shaft.

The vibrator shaft 86 is provided with a slot 91 for receiving a key 92,and the eccentric weight '83 has a hub 93 provided with a bore 94 forreceiving shaft 86 and with a similar slot 95 for receiving the key 92.The eccentric weight is thus fixedly mounted on the shaft 86 to rotatewith it.

The hub 93 supports at one side a weight 83, the specific shape of whichis shown in Figs. 2 and 5. Looking at the weight in elevation in Fig. 2,it will be observed that the weight is curved about its periphery, butit is provided with a relatively blunt point 96 at the front and theback. The weight tapers outwardly at 97 from the hub toward the pointedpart 96 and is substantially stream-lined from front to back from onepoint 96 to the other point. The weight is thus adapted to be rotated ineither direction, and is substantially stream lined so as to reduce theair resistance as much as possible and thus reduce the power required toeffect operation of the device.

All of the parts of the device are preferably so constructed that theymay be quickly manufactured upon a lathe and so constructed that all ofthe bearings will be in alignment when the device is assembled. Thus theend plates 61 are formed with outer fiat surfaces 98 which are annularin shape and bounded on the inner side by an annular cylindricalshoulder 99.

The vibrator housing has a complementary flat surface and an inwardlyprojecting annular part 100 which fits within the cylindrical shoulder99 in order to align the vibrator housing with the motor housing. Inorder to assure the alignment of these parts, the vibrator housing isplaced in the lathe, and the socket 84 may be cut or formed trulyconcentric with the housing, and while the housing is still held in thesame position, the surfaces 98 and 100 and the annular shoulder 99 maybe formed on the end housing.

The end plate 61 is likewise formed with its sockets 65, 67 and its bore63, annular shoulder 99, and annular shoulder 60, all of these partshaving the same axis. When the parts are assembled with the other partsof the motor housing, the bearing sockets are thus placed in substantialalignment with each other, and the separate motor and vibrator shaftsare substantially aligned so that they may be driven together.

The motor shaft is preferably formed at each end with substantiallytriangular axially extending lugs;101, 102 located diametricallyopposite to eachother and separated by the cut-out spaces 103, 104 whichcommunicate between the lugs 101, 102. See Fig. 6.

The vibrator shafts 86 each have one end similarly formed with lugs 105,106 and when the 107 is adapted to provide a universal connectionbetween the motor shaft and vibrator shafts. The fiber member 107 may beof leather, fiber, rubber, or any convenient material, and the ends ofthe shafts are slightly spaced, as shown at the right in Fig. 2, topermit universal movement.

A loose metal or rubber tubular casing 108 may surround the ends of theshafts at the universal joint to prevent the access of grease or otherlubricant to the fiber member.

The vibrator being provided with a separate shaft for each eccentricweight, there is no eccentric radial thrust placed upon the motor shaft,and the motor is capable of operation with a minimum amount of wear andtear on its bearings. Suitable larger bearings are provided for theeccentric weights, and each eccentric weight has a bearing at each endof its shaft. The eccentric weights preferably extend in the sameangular direction with respect to each other when they are assembledwith the motor and shaft so that they rotate together and tend to causethe vibrator to vibrate back and forth rather than to twist, but in someembodiments of the invention the eccentric weights may be oppositelydisposed to effect a twisting action of the vibrator.

Referring to Fig. 9, this is a modification in which the details ofconstruction of the motor housing and vibrator housing may besubstantially the same, with the following exceptions. The vibratorshaft 109 is provided with a bevel gear 110 having a weight 111eccentrically located at one side of the gear. The weighted gear 110 isfixedly secured to the shaft 109, shaft 109 being rotatably mounted uponsuitable anti-friction bearings 112, 113. Shaft 109 also supports theinner race of an anti-friction bearing 114, which rotatably supports asecond bevel'gear 115 on the shaft 109. p

The vibrator housing 74 in this embodiment is formed with a socket 116at one side for receiving an anti-friction bearing 117, which rotatablysupports a stub shaft 118 carried by a bevel gear 119'. Shaft 109 drivesgear 110 in one direction, and through the gear 119 the gear 115 isdriven in the opposite direction.

Gear 115 is likewise provided with an eccentric weight 119 at one side,by being thickened at one side, and the vibrator thus has two eccentricweights rotating in opposite directions.

These eccentric weights may be so arranged with respect to each otherthat they both reach the bottom shown in Fig. 10 at the same time or sothat the weight 111 is at the top when the weight 119 is at the bottom.

Referring to the arrows of Fig. 10, it will beobserved that when theweights are at the bottom,, weight 11 is passing toward the right, andweight 119 toward the left, and the inertia effects of the weights atthis point counteract each other. The same situation takes place whenthe weights are at the top of the circle in Fig. 10. When, however, theweights are at the'side points of the circle in Fig. 10, it will befound that weight 119 is passing upward when weight 111 is passingupward, and

thus the two weights work together to cause an inertia vibration in thesame direction. The combined weights,.therefore, tend to producevibrations in a vertical direction, as shown by the arrows 120.

In the arrangement of Fig. 11, the combined weights are additive in ahorizontal direction and produce vibrations in a horizontal direction,as shown by the arrows 121.

The present vibrator produces much better results than any of thevibrators which have previously been developed, and the higher rates ofvibration produce better grades of concrete and better results. Thepresent vibrator is capable of being vibrated at a very high rate andcapable of operation for a long period of time without overheatingor'requiring any repair.

It may be quickly removed from one form and. placed upon another form,each form carrying an appropriate keystone connecting block, and it isnot necessary to loosen or tighten any cables, bolts or securing devicesother than the keystone device,.which has a predetermined taper andwhich is quickly detached.

The heat generated by the operation of the device is quickly radiatedfrom the outside, and the motor is entirely enclosed so that dust andother foreign matter from concrete operations cannot get-into the motorand affect its operation. It is not necessary to provide for ventilationof the inside of the motor with the regular sizes of motors; but, ifdesired, in larger types of motors positive ventilation may also beprovided.

While I have illustrated a preferred embodiment of my invention, Icontemplate that many modifications may be made without departing fromthe spirit of the invention, and I do not wish to be limited to theprecise details of construction set forth, but desire to avail myself ofall changes within the scope of the appended claims.

* Having thus described my invention,,what I claim is new and desire tosecure by Letters Patent 1 5 of the United States, is:

1. In an electric'vibrator, the combination of a motor housingcomprising a pair of end plates, a pair of field clamping members, amultiplicity of laminations forming a motor field between said 120field'clamping members, bearings carried by each of said end plates; amotor armature and shaft, and auxiliary vibrating elements mounted oneach end of said motor casing and comprising a shaft with bearings ateach end and an eccentric weight mounted between said bearings, saidmotor shaft 1 and said vibrator shafts being provided with interlockinglugs on the ends of said shafts and nonmetallic elements disposedbetween said lugs,

said non-metallic element being substantially groove-formed in shape,and said lugs being substantially segmental, and the lugs on each shaftspaced from each other to provide space for said non-metallic element.

2. In an electric vibrator, the combination of a motor housingcomprising a pair of end plates,

a pair of field clamping members, a multiplicity of laminations forminga motor field between said field clamping members, bearings carried byeachof said end plates, a motor armature and shaft, and auxiliaryvibrating elements mounted on each end of said motor casing andcomprising a shaft with bearings at each end and an eccentric weightmounted between said bearings, said end plates each being formed withopposed angular grooves, the opposed faces of saidgrooves divergingdownwardly from each other for engagement with a complementary shapedanchoring memher, said eccentric weight being substantially stream-linedin shape, threaded members passthrough said end plates, clampinginembersand field laminations, and a handle substantially U shape carried by oneof said threaded.

members. I

3. In a vibrating apparatus for concrete, the combination of a formhaving a pair ot'substantially parallel angle irons attached thereto, achannelled metal member having a pair of flanges attached to said angleirons and having a supporing body joining said flanges, a tapered metalat t t member. carried by said channelled member, said tapered securingmember having plane wedging surfaces sloping outward from. each otherand sloping outward toward the bot-

